I have posted on and off for the last two years about the problems I had with my seat belt reminder system on my 99 Corolla and have tried various ways to fix that without success.

In 98-00 Corolla the car tells if you (as a driver) have buckled up via a retractor switch integrated with the seat belt assembly. When you pull it out enough, the contacts close and it tells the integration relay that you have buckled up. Its black cover can easily come loose, throwing off the rotating contacts inside, resulting in the reminder totally not on, or remains on even when you are wearing your seat belt. Starting 2001 the seat belt reminder operates off of the buckle; as a result the car will only turn off the seat belt reminder after really have buckled up.

My 97 Camry have always been like this, so are 93-97 and 03+ Corollas. So I don't know why Toyota would come up with such an idiotic contraption for 98-00.

This mod will change the retractor switch into a buckle switch so your system will be exactly like in a 01 or 02, and will root out this problem for good.

Anyway, here's the guide:

Parts list

2001 Corolla seat belt buckle 73230-02040-xx (C$24.50 bought from a local dealer, $14.14 on 1sttoyotaparts; There's a suffix for different color so check to make sure)

Connector plug 90980-10825 ($2.20 - metal contacts not included, see below)

A piece of 1/4" split loom

Two pieces of wire, preferably one red and one white

Electrical tape

Solder

Heat shrink tubing (optional but makes for a nice look)

Tools:

Soldering iron

12mm, 14mm socket, ratchet

Screwdriver

If your car is auto and you don't plan to convert it to manual like I do, you can find this connector under the dash. If you peek your head under the driver's seat and look up, you'll see two plugs dangling, one blue and one white. You want the white one. Pull it out as far as you can, then clip the plug out, keeping as long a lead with the plug as possible.

But if your car is manual, you have to buy the connector and see where you can get the two electrial contacts. Those two plugs would be connected to some switches there.

Torque: 30lb/ft.

Procedure

Buckle installation (easy):

1. Open rear console box (if you have it), remove carpet, undo two bolts.

2. Slide both seats all the way back to gain access to two additional screws. Undo them, and remove center rear console box. It takes some convincing and maneuvering to remove. It helps to pull your parking brake all the way up.

3. Remove one screw holding the plastic piece to the seat on the buckle side. Then remove it. You need to pry around it to free it.

4. Once exposed, remove the 14mm bolt holding the buckle.

5. Install new buckle, reinstall bolt, torque to 30 lb-ft.

6. Replace the plastic cover you took out in (3). Route the buckle switch wire downwards away. Make sure it isn't pinched. Reinstall screw.

7. Look under the seat for a small hole to clip the male jack into. Any hole that looks a small oval will do, but there would be only one that is within the jack's reach. Stick it in.

8. Reinstall center console. Replace two screws and two bolts, and the carpet.

Switch wire rerouting (hard):

1. Remove left side front scuff plate, driver left side kick panel, and left side lower pillar garnish. To remove the pillar garnish you have to open the rear left door and pull out a clip.

2. Remove the black bracket, held on by 3 screws, to gain some room to work with.

3. Unplug the retractor switch connector - The small white one!

4. Clip off the plug at its base, leaving all the wire behind. Bye bye retractor switch!!!

5. Solder the new wire to the existing wire. The new wire you use should allow 6" of wire to stick out of the heater duct opening under the driver seat. Then solder on the plug you clipped off before. If you are using heat shrink tubing, slide on a piece long enough to cover the solder joint BEFORE you solder it. Otherwise wrap the joint up with electrical tape.

6. The best way to route this new wiring is to go under the carpet cutout near the white clip closer to the tail, under the forward seat bolt, and out just above heater duct outlet. So cut loose the electrical tape on the floor wire between the seat belt and that cutout in the carpet. Separate the red wire from your ex-retractor switch from the bundle. Tape up the bundle again, include the white ground wire in this bundle if you wish.

7. Branch off the red and white/black lead from your ex-bundle switch at the carpet cutout. Wrap them together with electrical tape until about 6" from the new plug.

8. You will need to pull up the carpet a little, so free the floor wire from the two white clips, then, stick a flat screw driver vertically in the clip's slot, turn CCW a little, and lift the clips out. You need to free both clips.

9. If you lift up the carpet a bit and peek down, you'll see a yellow wire loom taking a turn underneath. Stick your 1/4" wire loom down there until 6" of it come out of the opening for heater duct.Leave the other end accessible. You'll stuff your new wire down it.

9. Undo the new plug. Use a 1mm flat screwdriver (you can get one in a precision screwdriver kit) to pry up the lock, then use it to pry up the hook and pull out the leads.

10. Now thread your new wire, with bare lead, down the split loom. Keep at it until the lead pops out the other end. Once both wires are completely through the loom, reinstall the connector. Press on the lock to secure it.

11. Thread the two wires underneath the carpet, make a turn behind the crossmember the seat mounts on. Pull out the wire loom a little so there's no bulge seen on the carpet. Replace carpet.

12. Connect the connector.

13. Test the connection. Turn ignition to ON. It should 'ding' and the seat belt reminder light should blink. Latch the seat belt and it should go out. Undo the belt and it should blink again.

14. If the connection is good. Reinstall everything that you took off.

The way I did it: (even harder)

I tore apart almost the entire left side of interior so that I can extract the whole ground wire (your white/black lead), originally routed all the way to the blue junction connector in the trunk. Once the wire is out, I soldered on two leads that I got from my other junkyard purchase (that one meant for my manual swap) and did the wire. Finally the ground wire is re-routed to a black 4-position junction connector (known as J1) up behind the instrument panel. The whole process took me 1.5 days. And I actually removed the seat to gain even more working room. If you do remove the seat, you may have to get two persons to ease the seat into position, there's two pegs in the front that will scratch up the finish by the seat mount very easily. Torque for seat bolts, as tested by my torque wrench, is 33lb-ft.

After all the hard work, this mod is a success, and I can finally say bye to the problem that bugged me for the last 2 years!